As world leaders meet in Copenhagen to draft legislation to rein in the release of greenhouse gases and stem climate change, an R.A. Hall Elementary School student is questioning the science supporting global warming.

“There is not enough evidence to prove global warming is occurring,” fourth-grader Julisa Raquel Castillo concluded in a science project she entered in the campus’ annual science fair on Tuesday.

Julisa studied temperatures in Beeville for the past 109 years to develop her conclusion.

She researched online data basis of the National Oceanic and Atmospheric Administration, or NOAA, the National Weather Service, and checked out books on climate change at the Joe Barnhart Bee County Library.

Her findings:

• temperatures rose and fell from 1900 to 1950.

• temperatures in Beeville cooled down over a 20-year period beginning in 1955 and ending in 1975.

• Since 2001, temperatures in Beeville have grown cooler year after year.

Close to 200 R.A. Hall students entered projects in this year’s science fair, said organizer Denise Salvagno, who also teaches the school’s gifted and talented students.

Fourth- and fifth-graders were required to enter projects as part of class work; however, students in grades first, second and third could enter projects if they desired.

Students in Ben Barris’ science club at A.C. Jones High School judged the projects.

“Some of these projects are pretty creative,” said Zachary Johnson, a senior at A.C. Jones and one of the judges. “You can tell a lot of the students put a lot of effort into their projects. Some of them didn’t put much effort into it but a lot of them did and, overall, I’m impressed with what I am seeing.”

Fourth-grader Kaleb Maguire proved that all tap water in Beeville was the same quality.

He took samples of water at 10 different sites across town and came to the conclusion that because the water originated at the same source — the city’s fresh water plant — the samples contained the same amount of alkalinity, pH and free chlorine.

Fourth-grader Amber Martinez concluded that worms subjected to music were more alert than those not.

And fourth-grader Sam Waters’ project was no doubt much enjoyed by his pet pooch, Lucky.

Sam wanted to know which meat his dog would like more. Turns out Lucky preferred chicken over both hotdogs and sausage.

Fifth-grader Savannah Gonzales found out that ants prefer cheese over sugar, but classmate Misty Nienhouse concluded that ants preferred sugar over cheese. Tessa Giannini’s science project also seemed to prove that ants preferred sugar over cheese, bread or anything else.

However, fourth-grader Faith Hernandez conducted a similar experiment and concluded ants preferred cheese over ham.

Nathanial Martinez, also a fourth-grader, built a working seismograph and demonstrated how it detected and recorded earthquakes.

Fifth-grader Jamison Hunter decided to see if money in the hand made a difference in someone’s heart rate.

He recorded the heart rate of each volunteer without money in their hand, with one dollar bill in their hand, two one dollar bills in their hand and three one dollar bills in their hand.

His conclusion: “From this experiment, I learned that everyone’s heart rate is different by how much money they hold,” he said. “No two people had the same results even with the test being done the same way.”